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Thermal Conductivity Measurement of Saturated Clayey Mixtures using Oedometer Consolidation and Constant Rate of Strain Consolidation Tests

표준압밀시험 및 일정변형율 압밀시험 결과를 이용한 포화된 혼합 점성토의 열전도계수 측정에 관한 실험적 연구

  • Kim, HakSeung (School of Civil and Environmental Engineering, Kookmin University) ;
  • Kwon, HyungSeok (School of Civil and Environmental Engineering, Kookmin University) ;
  • Lee, Jangguen (Geotechnical Engineering & Tunnelling Research Division, Korea Institute of Construction Technology) ;
  • Cho, Nam Jun (School of Civil and Environmental Engineering, Kookmin University) ;
  • Kim, Hyun-Ki (School of Civil and Environmental Engineering, Kookmin University)
  • 김학승 (국민대학교 건설시스템공학부) ;
  • 권형석 (국민대학교 건설시스템공학부) ;
  • 이장근 (한국건설기술연구원 Geo-인프라연구실) ;
  • 조남준 (국민대학교 건설시스템공학부) ;
  • 김현기 (국민대학교 건설시스템공학부)
  • Received : 2012.07.18
  • Accepted : 2012.08.13
  • Published : 2012.09.28

Abstract

Thermal distribution in soils must be considered in engineering designs and constructions, including estimates of frost heave and thaw settlement, infrastructure in cold regions, and geothermal systems. Because thermal conductivity is a key parameter for evaluation of thermal distribution in soils, it must be accurately estimated. The thermal conductivity of fine-grained soils has been widely studied in recent years; however, few studies have reported a reliable method for experimental measurement. The present study presents the results of an experimental investigation of the thermal conductivity of a saturated kaolinite-silica mixture with respect to the variation of dry density. Thermal conductivities were measured in Constant Rate of Strain (CRS) consolidation tests, and the experimental data were analyzed to evaluate the accuracy of the new measurement system. In addition, we present an evaluation method for predicting thermal conductivity in fine-grained soils.

지반 내 열전도 현상은 지구온난화에 따른 지반거동 변화 예측, 극한지 기반시설 건설, 지열 냉난방 시스템의 부하 계산 등 다양한 건설 및 환경 분야에서 중요한 고려사항이다. 열전달 해석에서 가장 중요한 변수인 열전도계수를 산정하는 방법으로 이를 정량적으로 정확하게 예측, 평가할 수 있는 기법의 필요성이 제기되고 있다. 최근 들어서는 세립토를 대상으로 열전도계수에 관한 연구가 활발하게 진행되고 있다. 그러나 기존 연구자들은 세립토의 열전도계수를 정확히 측정하는데 어려움으로 인해 신뢰성 있는 데이터가 부족하다는 문제점들이 제기되고 있다. 본 연구에서는 포화된 카올리나이트와 실리카 혼합점성토를 대상으로 건조밀도 변화에 따른 열전도계수 측정 실내실험을 수행하였다. 표준압밀시험의 단점을 보완한 일정변형율 압밀시험 자동화 장비를 이용하여 건조밀도의 변화에 따른 열전도계수를 연속적으로 측정하고 실내실험 결과의 신뢰성을 분석하였다. 또한, 기존 경험식과의 비교를 통해 최적의 세립토 열전도계수 예측 방법을 제시하고자 한다.

Keywords

Acknowledgement

Supported by : 한국건설기술연구원

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